Buggy code:
public final class ServerFactory { private ServerFactory ( ) { } @ SuppressWarnings ( { "RawUseOfParameterizedType" } ) public static void combine ( DomainModel domainModel , HostModel hostModel , String serverName , List < AbstractServerModelUpdate < ? > > list ) { final ServerElement serverElement = hostModel . getServer ( serverName ) ; if ( serverElement == null ) { throw new IllegalArgumentException ( ( ( "Host<seq2seq4repair_space>model<seq2seq4repair_space>does<seq2seq4repair_space>not<seq2seq4repair_space>contain<seq2seq4repair_space>a<seq2seq4repair_space>server<seq2seq4repair_space>named<seq2seq4repair_space>'" + serverName ) + "'" ) ) ; } final String serverGroupName = serverElement . getServerGroup ( ) ; final ServerGroupElement serverGroup = domainModel . getServerGroup ( serverGroupName ) ; if ( serverGroup == null ) { throw new IllegalArgumentException ( ( ( "Domain<seq2seq4repair_space>model<seq2seq4repair_space>does<seq2seq4repair_space>not<seq2seq4repair_space>contain<seq2seq4repair_space>a<seq2seq4repair_space>server<seq2seq4repair_space>group<seq2seq4repair_space>named<seq2seq4repair_space>'" + serverGroupName ) + "'" ) ) ; } final String profileName = serverGroup . getProfileName ( ) ; final ProfileElement leafProfile = domainModel . getProfile ( profileName ) ; if ( profileName == null ) { throw new IllegalArgumentException ( ( ( "Domain<seq2seq4repair_space>model<seq2seq4repair_space>does<seq2seq4repair_space>not<seq2seq4repair_space>contain<seq2seq4repair_space>a<seq2seq4repair_space>profile<seq2seq4repair_space>named<seq2seq4repair_space>'" + profileName ) + "'" ) ) ; } Set < String > unspecifiedInterfaces = new HashSet < String > ( ) ; Map < String , InterfaceElement > interfaces = new HashMap < String , InterfaceElement > ( ) ; for ( InterfaceElement ie : domainModel . getInterfaces ( ) ) { if ( ie . isFullySpecified ( ) ) interfaces . put ( ie . getName ( ) , ie ) ; else unspecifiedInterfaces . add ( ie . getName ( ) ) ; } for ( InterfaceElement ie : hostModel . getInterfaces ( ) ) { interfaces . put ( ie . getName ( ) , ie ) ; unspecifiedInterfaces . remove ( ie . getName ( ) ) ; } for ( InterfaceElement ie : serverElement . getInterfaces ( ) ) { interfaces . put ( ie . getName ( ) , ie ) ; unspecifiedInterfaces . remove ( ie . getName ( ) ) ; } for ( InterfaceElement interfaceElement : interfaces . values ( ) ) { list . add ( new ServerModelInterfaceAdd ( new org . jboss . as . model . socket . InterfaceAdd ( interfaceElement ) ) ) ; } SocketBindingGroupRefElement bindingRef = serverElement . getSocketBindingGroup ( ) ; if ( bindingRef == null ) { bindingRef = serverGroup . getSocketBindingGroup ( ) ; } SocketBindingGroupElement domainBindings = domainModel . getSocketBindingGroup ( bindingRef . getRef ( ) ) ; if ( domainBindings == null ) { <START_BUG> domainBindings = new SocketBindingGroupElement ( domainBindings ) ; <END_BUG> } int portOffset = bindingRef . getPortOffset ( ) ; final Set < String > extensionNames = new LinkedHashSet < String > ( ) ; for ( String name : domainModel . getExtensions ( ) ) { extensionNames . add ( name ) ; } for ( String name : hostModel . getExtensions ( ) ) { extensionNames . add ( name ) ; } for ( String name : extensionNames ) { list . add ( new ServerExtensionAdd ( name ) ) ; } for ( AbstractSubsystemElement < ? extends AbstractSubsystemElement < ? > > subsystemElement : leafProfile . getSubsystems ( ) ) { ServerFactory . processSubsystem ( ( ( AbstractSubsystemElement ) ( subsystemElement ) ) , list ) ; } for ( ServerGroupDeploymentElement element : serverGroup . getDeployments ( ) ) { final ServerModelDeploymentAdd add = new ServerModelDeploymentAdd ( element . getUniqueName ( ) , element . getRuntimeName ( ) , element . getSha1Hash ( ) , element . isStart ( ) ) ; list . add ( add ) ; } } private static < E extends AbstractSubsystemElement < E > > void processSubsystem ( E subsystemElement , List < AbstractServerModelUpdate < ? > > list ) { } }

Fix:
domainBindings = new SocketBindingGroupElement ( "domainBindings" ) ;